Interlocking system for railroads



March 14, 1939; s. N. WIGHT INTERLOCKING SYSTEM FOR RAILI QOADS Filed Dec. 18, 1937 2 Sheets-Sh getl- March 14, 1939. s. N. WIGHT INTERLOCKING SYSTEM FOR RAILROADS 2 Sheets-Sheet 2 Filed Dec. 18, 1937 INVENTEZZ BY $2 ATTORNEY Patented Mar. 14, 1939 UNITED STATES PATENT OFFICE 2,150,868 INTERLOCKING SYSTEM FOR RAILROADS Application December 18, 1937, Serial No. 180,615

14 Claims.

This invention relates to trafiic controlling systems for railroads, and more particularly pertains to a system of electric interlocking of the entrance-exit type.

5 In a system of the entrance-exit type, it is expedient to provide a control panel having control buttons for the entrance and exit ends of the routes, for controlling track switches and signals associated with a track layout by designating only the entrance and exit ends of the particular route desired to be set up. This invention provides a means, dependent upon the distinctive position of the entrance buttons, for selecting different classes of signals, as well as for determining the effectiveness of automatic means for restoring the parts of the system used in setting up each route to a normal position upon passage of a train.

When an entrance button is depressed and restored to its normal position, a high or medium speed signal is selected and automatic restoration is rendered effective upon the passage of a train; when the entrance button is rotated to a position where its marker is at the top of the button, a high or medium speed signal is selected and automatic restoration is ineffective; when the entrance button is rotated to a position where its marker is at the bottom of the button, low speed signals are selected and automatic restoration is ineffective; and when the entrance button is pulled out from a normal position with respect The clearing of the signal selected by the distinctive actuation of an entrance button requires the setting up of a route by also actuating an exit but-ton.

Modifications of the above mentioned forms of control are provided to meet varying requirements of practice, such as the rendering effective of the automatic restoration of routes upon the passage of trains governed by high or medium speed signals at all times with automatic L5 restoration rendered ineffective for low speed signals, and automatic restoration upon the passage of trains rendered eifective at all times for routes governed by either class of signals selected.

Another object of this invention is to provide a plurality of indications within the entrance button which are made distinctive by the energization of different colored lamps with either constant or interrupted energy.

Other objects, advantages and characteristic features of the present invention will in part be apparent from the accompanying drawings, and in part pointed out as the description of the invention progresses.

In describing the invention in detail, reference will be made to the accompanying drawings, in which like reference characters (provided with distinctive exponents) designate corresponding parts throughout the several views and in which:

Fig. 1 shows one embodiment of the present invention as applied to the governing of the movement of trains over a simple track layout; and

Figs. 2 and 3 show modified forms for parts of the system shown in Fig. 1.

For the purpose of simplifying the illustrations and facilitating in the explanation thereof, the various parts and circuits constituting the embodiment of the invention have been shown diagrammatically and certain conventional illustrations have been employed, for the purpose of facilitating the disclosure with respect to the principles and mode of operation, rather than for illustrating the specific construction or arrangement of parts that would be employed in practice. Thus, the various relays and their contacts are illustrated in a conventional manner, and the symbols and are used to indicate connections to the positive and negative terminals respectively of batteries, or other sources of electrio current, instead of showing all of the wiring connections to these terminals.

With reference to the accompanying drawings, a stretch of single track has been shown as having been connected to a turnout track by the track switch TS, and signals have been provided for governing trafiic in both directions, signal H1 having been provided for governing east bound traflic, and signals H and i2 having been pro vided for governing west bound traffic.

Signal ID is made up of three different units, signal A having been provided for governing high speed trains for the route from signal ID to signal l2, signal HJB having been provided for governing medium speed trains from signal NJ to signal II, and signal lElC' having been provided for governing low speed train movements over either of the above mentioned routes.

A track section 2 is provided with a track relay 2T which is controlled by the usual track circuit having a track battery, and the track switch TS is assumed to be properly bonded to provide the usual fouling protection.

A switch machine SM is provided for the track switch TS, and it may be of any suitable type such, for example, as the type disclosed in the patent to W. K. Howe, No. 1,466,903, dated September 4, 1923.

The relay WP is provided in the usual man- 'ner for repeating the position of the switch points.

in correspondence with the position of the operating mechanism of the switch machine SM, in the normal and reverse locked positions.

The signals may be of any suitable type, such, for example, as the searchlight type of signals which have been shown, and the usual red indication is provided for danger when the'signal mechanism is deenergized, and the green indication is provided for clear when the signal mechanism is energized.

The control panel provided in the control office may be of any suitable type, having a miniature track diagram constructed thereon, representative of the actual track layout in thefield, and having entrance and exit buttons provided on the track diagram at points representative of actual entrance and exit points in the track layout.

The entrance button NB can be of the type shown, for example, in the applicatiton of J. F. Merkel, Ser. No. 158,720, filed August 12, 1937. This type of control button has a commutator carrying contact segments which close circuits between various contacts when the button NB is rotated 90 in either direction from a normal position. There is also a pair of contacts on the control switch, operated by the button NB, which are closed when the button is in the normal position, and which are opened when the button NB is pulled out from a normal position or is rotated in either direction from normal. Another pair of contacts are closed only when the button NB is depressed from a normal position, and these contacts are opened as soon as the button NB is restored to a normal position in which it is biased with respect to push and pull movement.

The exit buttons XB are of the self-restoring type, and the depression of each exit button after the operation of an entrance button for the opposite end of that route causes the positioning 'of switch control relays in accordance with the route being set up.

A relay NR is provided for each entrance point in the track layout, and the picking up of that relay defines the entrance point for the selfselecting network of switch control relays.

The relay OR is used in an obvious manner for selecting the control of the low-speed signal HJC as well as for serving in a similar capacity to the relay NR under certain conditions.

Although the invention has been shown as having been applied to a self-selecting network of the type shown, for example, in the prior application of Langdon, Ser. No. 176,466, filed November 26, 1937, .it is to be understood that this invention could as well be applied to systems employing other types of self-selecting networks which require the defining of an entrance point by a relay which can be controlled in such a manner as to include the principles set forth in this disclosure.

Due to the fact that this invention is primarily concerned with the control of the apparatus associated with the various entrance points, little reference will be made to the detail of the operation of the self-selecting network and the control of the switch machine SM. in accordance with the position of the switch control relays N and R, all of which details have been clearly shown and described in the above mentioned prior Langdon application.

It is believed that the nature of the invention, its advantages and characteristic features, can

best be understood by considering the system from the standpoint of operation.

Operation Under normal conditions all of the relays for the self-selecting network are deenergized, the track relay 2T is of course energized when the track section is unoccupied, and the correspondence relay NCR or RCR, depending upon the last operated position of the track switch, is in its picked up position.

Normally the buttons NB on the control panel are in their normal position as shown, with the round marker on the knob in alignment with the indicating arrow on that button and the section of the miniature track diagram representing the track in the field with which the button is associated.

The control switch contacts for the entrance and exit buttons have been shown as having been associated with their respective buttons by dotted lines, and such contacts have been represented diagrammatically in order to more clearly illustrate the selection of the circuits with which they are associated, the commutators carrying contact segments for the control switch controlled by the button IBNB having been shown as C and C and they operate degrees in a clockwise or counterclockwise direction from the normal position shown in accordance with corresponding move- I ment of the button HJNB.

With button lllNB in a normal position, the operator can initiate the setting up of a route from signal if! to either signal i l or signal 12, in such a manner that the relays of the self-selecting network for that route will be restored to their normal position upon passage of a train, by the depression of button IUNB.

In considering the details of the various means for energizing relay HlNR, for initiating the setting up of routes, assume the operator to initiate the setting up of a route by the depression of button lGNB, with the various parts of the system in the above described normal position.

The depression of button IONB from a normal position closes a circuit for energizing relay IDNR from through a circuit including, front contact 20 of relay- 2T, contacts 2| of controller C contact 22 of button IONB in a depressed position and upper winding of relay HINR, to

After the button IUNB is restored from its depressed position to its normal position, a stick circuit is closed for holding relay IONR in a picked up position, from (-F) through a circuit including front contact 20 of relay 2T, contacts 2| of controller C contact 22 of button IQNB in a normal position, front contact 23 of relay IONR and upper winding of relay lUNR, to

The picking up of relay IBNR, followed by the depression of an exit button for a route emanating from that entrance point, such as button IZXB, for example, causes the energization of the proper switch control relays for positioning the track switch TS in accordance with the route being set up.

The joint operation of buttons IDNB and I2XB closes a circuit for energizing relay iZXR from through a circuit including front contact 24 of relay IUNR, back contact 38 of relay IIJXR, back contact 39 of relay R, winding of relay IZXR, back contact 40 of relay NR, and con,- tact M of button I2XB in a depressed position. The picking up of that relay closes a stick circuit through a circuit including front contact 42, for maintaining relay I2XR. in a picked up 2,150,868- position after the button I2XB is restored to normal.

The picking up of relay I ZXR closes an obvious circuit at front contact 43 for energizing the upper winding of relay N. The picking up of relay N causes the operation of the switch machine SM to a normal position through a medium of switch control and electric locking relays, all of which can be provided in a number of ways as has been shown in prior applications such as the above mentioned Langdon application.

If the track layout is more complex than the simple layout shown so as to require a form of route locking, the route locking means shown in the above mentioned Langdon application can be employed, whereby a winding is provided on the N and R relays for maintaining them in their picked up position so long as the route locking is eifective for the route with which those relays are associated. In maintaining the N and R relays in their picked up position as long as the route locking is effective, the nature of the route locking is such that pro-conditioning of the network is prevented.

Upon completion of the operation of the track switch TS to a normal position in accordance with the route being set up from signal It! to signal l2, relay NCR is energized from through a circuit including front contact 44 of relay WP, polar contact 45 of relay WP in a right-hand position, back contact 46 of relay R and winding of relay NCR, to The picking up of relay NCR closes a circuit for energizing relay IOG from through a circuit including front contact 4'! of relay IZXR, front contact 48 of relay NCR, back contact 49 of relay lflXR, front contact 58 of relay I ONE, and winding of relay IGG, to and the picking up of relay lUG closes a circuit for energizing signal 10A from through a circuit including front contact of relay NCR, back contact 30 of relay IUCR, front contact 52 of relay IOG, front contact 31 of relay 2T, and mechanism of signal IDA, to

After signal IDA has been cleared for a route from signal In to signal l2, the entrance of a train into track section 2 causes the dropping away of relay 2T, which in turn causes the restoration to normal of the parts of the system associated with setting up that route and also causes the restoration of signal IDA to stop.

The dropping of relay 2T opens the stick control circuit for relay IDNR at front contact 20 so as to cause the dropping away of that relay, and the opening of the control for the XR relay for that route at front contact 24, thus causing the relays of the system associated with that route to be restored to their normal position, all in a manner which is obvious from the accompanying drawings and which has been described in detail in the above mentioned prior Langdon application.

Signal I0 is, of course, restored to stop as soon as its control circuit is opened at front contact 37 of relay 2T.

The dropping of relay 2T also opens the control circuit for relay ZTP, thus causing that relay to close a part of the stick circuit for relay lllNR through back contact l9, so as to allow for the setting up of the same route for a following train, while the first train is still in track section 2.

It is obvious, therefore, that the operator can initiate the setting up of a route for the following train in identically the same manner as has been described, the stick circuit for relay IONR having been closed through a circuit including back contact I 9 of track repeater relay ZTP. Signal Ill, under such conditions, will of course remain at stop until the first train has left track section 2.

It is readily apparent that the use of the relay TP in closing the stick circuit for relay IONR while track section 2 is occupied, is an optional feature withrespect to the operation of the system, and that only the front contact of relay 2T is required, if provision is not made for setting up the route for a following train while the preceding train is still on the detector track section.

After a route has been set up, due to the initiation in the above described manner, the operator can manually cause that route to be restored to normal by pulling out the button HINB, thus opening the stick circuit for relay NR when contact 22 associated with that button is in a pulled-out position. The opening of the stick circuit will, of course, cause relay IUNR to drop away and cause the restoration of the relays for that route to be effective.

The operator has a choice of whether or not he Wishes a' route for a high or medium speed signal to be automatically restored to normal upon the passage of a train, by the position of the button I UNB with respect to rotation. If he rotates the button 90 in a clock-wise direction from a normal position, a circuit is closed for energizing the lower winding of relay IDNR from (-1-), through a circuit including contact 25 of commutator C contact 26 of commutator C and lower winding of relay lliNR, to The picking up of relay HiNR of course initiates the setting up of a route in the same manner as has been typically described for a route from signal [0 to signal l2.

t is obvious that the relay Hi NR, when energized with the button lflNB rotated in a clockwise direction, remains energized as long as the button I ilNB remains in that position, thus maintaining the route with which it is associated, independent of the passage of trains over that route.

To restore a route to normal which has been set up by the operation of the button IONB in a clockwise direction, the operator has only to restore the button to a normal position, with respect to rotation.

Although the stick circuit for relay IBNR, including contacts 2! of commutator C is closed only when the button is in a normal position, with respect to rotation, there is a possibility thatthe button could be restored to normal from a rotated position in time to close the stick circuit for relay ifiNR before that relay had time to drop away. To insure the dropping of relay ltlNR upon restoration of the button lElNB from a clockwise operated to a normal position, the two windings of relay IGNR are oppositely connected, so that the closing of the stick circuit for the upper Winding of that relay under such conditions causes the setting up of a flux in that relay opposing that produced by the energization of the lower winding, thus causing that relay to drop away and restore the relays for the route with which it is associated to a normal position.

It is, of course, obvious to those familiar with the art that relay IGNR could as well be a single winding relay and be energized from a battery having a mid-tap, thus effecting the same mode of operation of the system and the same GIl assurance of the dropping away of relay HINR upon restoration of that button to normal from a rotated position.

Having described the setting up of a route from signal I!) to signal l2 and the clearing of signal IDA, it is to be understood that such mode of operation is typical of that employed in setting up a diverging route and in clearing signal [0B, the selection of the two signals being provided in accordance with the position of the correspondence relay NCR and RCR.

If the operator rotates the entrance button HINB in a counter-clockwise direction from the normal position, he can select the control of the call-on signal I00, and at the same time provide that automatic restoration of the route with which'that signal is associated will be inefiective because relay l0CR is controlled directly in accordance with the position of the entrance button.

The rotation of the button HINB in a counterclockwise direction closes a circuit for energizing relay IOCR from through a circuit including contact of commutator C contact 21 of commutator C and winding of relay "ICE to The picking up of relay lilCR applies energy to the circuits of the self-selecting network through a circuit including front contact 28 of relay GB and back contact 23 of relay iGNR. The relay IOCR in addition to initiating the setting up of a route, closes a circuit through front contact 29 for energizing signal Hi0, and opens the circuits for signals IDA and WE at back contacts 35 and 3| respectively.

To restore a route which has been set up for a low speed or call-on signal, the operator re stores the button IUNB to a normal position, with respect to rotation, thus breaking the energizing circuit for the relay 1 OCR, and causing that relay to initiate the restoration of the rest of the relays forthat route to their normal position.

With minor changes in the construction of the entrance button shown in the above-mentioned prior application of J. F. Merkel, other combinations of selections can be provided, as shown in Figs. 2 and 3. 7

With reference to Fig. 2 it will be noted that the connection used for the distinctive control of relay HINR when the button is rotated in a clockwise direction from the normal position, has been eliminated, thus causing the high and medium speed signals 10A and 10B, and the relays for the routes with which they are associated, to be automatically restored to their normal position upon passage of a train over that route, the operator having no choice as to the'eifectiveness of the automatic restoration. The operation of the button IONB in a counter-clockwise direction from the normal position closes a circuit for energizing relay IIJCR. through the same circuit as has been heretofore described, and the picking up of that relay closes a circuit for energizing relay IBNR from through a circuit including contact 25 of commutator C contact 27 of com mutator C front contact 3;! cl relay MGR. and

" winding of relay IDNR, to The picking up of relay IDNR initiates the setting up of a route in the same manner as that heretofore described. With this type of control for relay NR it is necessary to pull the button out in order to restore the network to normal for a route whenever that button is restored to normal from a rotated position.

Should automatic restoration be required to be effective upon, passage of a train at all times, for

' m1 classes of signals, the circuits shown in Fig. 3,

can be used, in which relay IONR is energized through the same circuits as shown and described in Fig. 2 except that the part of the circuit including front contact 32 of relay IOCR. (Fig. '2) is eliminated. Thus, the operator must rotate the button in a counter-clockwise direction and then depress that button in order to initiate the setting up of a route for a. low speed signal. It is obvious that relay IDNR is maintained only by a stick circuit which includes contacts. 29 and IQ of relays 2T and ZTP respectively, thus causing the automatic restoration of each route, independent of the position of the button IUNB with respect to rotation.

Associated with each entrance button is two indicator lamps having distinctive colors such as red and white. within the center of the entrance button as shown, for example, in the above-mentioned prior application of J. F. Merkel, Ser. No. 158,720, filed August 12, 1937.

Under normal conditions the red lamp is energized with constant energy toindicate that the signal associated with that entrance button is at stop and that the parts of the network system associated with routes emanating from that entrance point are in their normal position. Under such conditions, red lamp RSK is energized from through a circuit including back contact 53 of relay IDNR, back contact 54 of relay IOCR, back contact 55 of relay IDG, and lamp RSK, to

As soon as the operator causes the picking up of relay IDNR, lamp RSK is energized with frequently interrupted energy to produce a fiashing eliect, from through an interrupter such as back contact 56 of flashing relay F, front cone tact 53 of relay IBNR, back contact 54 of relay IOCR, back contact 55 of relay [8G and lamp RSK, to 7 The picking up of relay IOGfor clearing a signal at signal 10, de-energizes lamp RSK by opening its circuit at back contact 55, and at the same time closes a circuit for energizing white lamp WSK with constant energy from through a circuit including front contact 51 of relay IBG and lamp WSK to It is obvious that the picking up of relay IIICR for a call-on signal, effects the display of similar indications to those just described when relay IONR is energized.

Having described a means for governing the passage of trains over a simple track layout as one specific embodiment of the invention, it'is desired to be understood that this form is selected to facilitate in the disclosure of the invention rather than to limit the number of forms it may assume; and, it is to be further understood'that various modifications, adaptations, and alterations may be applied to the specific forms shown to meet the requirements of practice, without in any manner departing from the spirit or scope of the present invention except as limited by the appending claims.

What I claim is:

1. In a switch and signal control system of the character described, a track layout having.

a first stretch of track connected to a second stretch of track by a track switch, a signal for governing traflic over said track switch, a track circuit for the section of track in advance of said signal, an entrance button'for said signal operable by rotation from a. normal position to a rotated controlling position and operable to a depressed controlling position from said normal These lamps are contained' position, being automatically restored to said normal position from said depressed position, an exit button for a point at the opposite end of said track layout from said signal, a relay for said entrance button, a circuit for energizing said relay when said entrance button is depressed from said normal position, a stick circuit for maintaining said relay in a picked up position only so long as said track relay is picked up and only provided said entrance button is in said normal position, a circuit for energizing said entrance relay whenever said button is in said rotated position, and circuit means responsive to the picking up of said relay combined with the depression of said exit button for causing the proper positioning of said track switch and the clearing of said signal, said circuit means being energized only so long as said relay is picked up.

2. In a switch and signal control system for railroads; a track layout including a track switch providing routes between an entrance point and a plurality of exit points; a, signal for said entrance point, a track section in advance of said signal; an entrance button for said entrance point having a stay-where-put operating position when rotated from a normal position, having an operating position when depressed from said normal position, being self-restored to normal from said depressed position, and being operable to a pulled-out from normal position from which it is self-restored to normal; an exit button for each of said exit points; a relay; a circuit for energizing said relay with one polarity whenever said button is in a rotated operating position from normal; a circuit for energizing that relay with the opposite polarity when said entrance button is in a depressed from normal operating position; a stick circuit for energizing said relay with said opposite polarity only so long as said track section is unoccupied, whereby said relay is maintained energized when said button is restored to normal from a depressed position and is dropped away by the reversal of polarity when said button is restored to that normal position from a rotated operating position; circuit means responsive to the picking up of said entrance relay jointly with the operation of one of said exit buttons for causing the proper positioning of said track switch and the clearing of said signal for a route between said entrance and exit points with which that relay and that exit button are associated, said circuit means being energized only so long as said relay is picked up, whereby said signal and said means for positioning said track switch are restored to normal when said entrance relay is dropped away; and means for opening said stick circuit when said button is pulled out from its normal position.

3. In a switch and signal control system for railroads; a track layout including at least one track switch for providing a plurality of routes; a single for governing trailic over at least one of said routes; a detector track section in advance of said signal; an entrance button associated with said signal and constructed to be manually operable to a rotated position from a normal position in which rotated position it remains until manually restored, and to be manually operable to a depressed position and a pulled-out position from said normal position, said button being spring biased so as to be automatically restored to said normal position from said depressed and pulled-out positions; an exit button associated with the leaving point of the route at the entrance to which said signal is located, said exit button being of the self-restoring type; an entrance relay for said entrance button; a pick-up circuit for energizing said entrance relay when said entrance button is momentarily operated to a depressed position; a stick circuit for maintaining said entrance relay in a picked up position dependent upon the unoccupied condition of said detector track section; a circuit for energizing said entrance relay whenever said entrance button is in a rotated position; means for opening the pick-up circuit of said entrance relay when said entrance button is in a pulled-out position;

an exit relay, a pick-up circuit for said exit relay closed by the momentary operation of said exit button; route establishing means responsive to the picking up of said entrance and exit relays for causing the operation of said track switch from its existing position to a position to set up said route defined by said entrance and exit buttons and for causing the clearing of said signal after said route has been set up, and a stick circuit for said exit relay closed dependent upon the picked up condition of said entrance relay.

4. In a trail-1c controlling system for railroads;

a track layout providing a plurality of routes between an entrance point and a plurality of exit points, a track switch included in said track layout, a signal for governing traific over said track switch, a track section in advance of said signal, a track relay and a slow acting track repeater relay for said track section, an entrance button for said entrance point having an operating position by rotation distinctive from a position and having a depressed operating posian entrance relay, a circuit for energizing said entrance relay when said entrance button is in said operating position by rotation, a circuit for energizing said entrance relay when said entrance button is in said depressed operating position, a stick circuit for maintaining said entrance relay in a picked up position when said entrance button is in said normal position, said stick circuit being interrupted when said track relay is dropped away and said track repeater relay is picked up, whereby said entrance relay is dropped away upon entrance of a train into said track section and the dropping away of said track repeater relay allows the energization of said entrance relay for initiating the setting up of a route for a following train even if the detector track section remains occupied, and circuit means responsive to the picking up of said entrance relay jointly with the depression of said exit button for causing the proper positioning of said track switch and the clearing of said signal, said circuit means being energized only so long as said entrance relay is picked up,

' whereby said signal and said means for positioning said track switch are restored to normal when said entrance relay is dropped away.

5. In a traffic controlling system for railroads; a track layout having a track switch for providing a plurality of routes between entrance and exit points; a signal having high and low speed aspects at a given entrance point; a track section in advance of said signal; an entrance button for said given entrance point operable by rotation to a controlling position, operable by depression to another controlling position and operable to a pulled-out position to open contacts normally closed when that button is in a biased to normal position with respect to push and pull operation;

normal operating selecting relay whenever said entrance button is operated to said controlling position by rotation;

an entrance relay for said givenentrance point; a circuit for energizing said entrance relay when ever said selecting relay is picked up; a circuit for energizing said entrance relay when said entrance button is depressed; a stick circuit maintained energized for said entrance relay only so long as said track section is unoccupied; circuit means responsive to the picking up of said entrance relay jointly with the depression of said exit button for positioning said track switch and clearing said high speed signal when said selecting relay is dropped away and for clearing said low speed signal when said selecting relay is picked up, said circuit means being energized only so long as said entrance relay is picked up; whereby said signal and said circuit means are restored to their normal position upon passage of a train; and means for opening said stick circuit for said entrance relay when said button is pulled out from a normal position.

6. In a traflic controlling system for railroads,

a track layout providing routes between entrance and exit points by having a track switch, a detector track section associated with said track switch, a track relay for said detector track section, a signal at a given entrance point and having high and low speed aspects, an entrance button for said given entrance point operable by rotation to a rotated controlling position from a normal position, operable by depression to another controlling position from said normal position, and operable to a pulled-out position from said normal position to open contacts closed when that button is in said normal position to which it is biased with respect to push and pull operation, an exit button for an exit point at the opposite end of a route from said given entrance point, a selecting relay for said signal, circuit means for energizing said selecting relay when said entrance button is operated to said controlling position by rotation, an entrance relay for said given entrance point, a circuit for energizing said entrance relay when, said entrance button is depressed, a stick circuit for maintaining said entrance relay in a picked upposition only so long as said detector track section is unoccupied, circuit meansresponsive to the picking up of said entrancerelay jointly with the depression of said exit button for positioning said track switch and clearing said high speed signal when said selecting relay is dropped away and for clearing said low speed signal when said signal selecting relay is picked up, said circuit means being energized only so long as said entrance relay is picked up, and means for deenergizing said entrance relay when said entrance button is pulled out from its normal position.

7. In a trafiic controlling system for railroads,

a button operable from a normal position to a ro-' tated controlling position in which it remains until manually restored and also operable to a depressed, controlling position and a pulled-out position from said normal position to which it is biased with respect to push and pull movement, a neutral relay, a circuit for energizing said neutral relay with one polarity when said button is in said rotated position, a circuit for energizing said relay with the opposite polarity when said button is in said depressed position, a stick circuit for energizing said relay with said opposite polarity when said button is in said normal position, automatic means for at times opening said stick circuit, means for opening said stick circuit when said button is in its pulled-out position, and a trafilc controlling device governed by said relay, whereby said relay is maintained in an energized position dependent upon said automatic means when said button is restored to normal from. a depressed position is dropped away when said button is restored 'to saidnormal position from said rotated position.

8. In a traffic controlling system for railroads;

a control button manually operable from a. normal position to a rotated controlling position in which it stays where put until manually restored, and also manually operable to a depressed controlling position from which it is biased toward said normal position; a neutral relay; a pick-up circuit for said neutral relay energized with one polarity when said button is manually operated tosaid rotated position; a pick-up circuit for said relay energized with the opposite polarity when said button is manually operated to said depressed position; a stretch of railway track including a track circuit; a signal governing traflic over said stretch of track; a stick circuit for energizing said relay with said opposite polarity when said button is in said normal position, said stick circuit ineluding a contact which is opened when said button is manually operated to said rotated position and also including a contact closed only when said track circuit is unoccupied; and a circuit for clearing said signal including a front contact of said neutral relay; whereby said neutral relay is maintained energized dependent upon the condition of occupancy of said track section when said button is self-restored to said normal position from said depressed position so that said signal is automatically restored to stop by the dc energization of said relay upon the opening of its stick circuit by the entrance of a train into said track section, and whereby said relay is dropped away when said button is manually restored to said normal position from said rotated positionby reason of the momentary opposite energization of its stick circuit. 7

9. In a traffic controlling system for railroads, a button operable from a normal position to a rotated controlling position in which it remains until manually restored, and also operable to a depressed controlling position from said normal position to which it is biased with respect to operation by depression, a neutral relay, a circuit for energizing said neutral relay with one polarity when said button is in said rotated position, a circuit for energizing said relay with the opposite polarity when said buttonis in said depressed position, a stick circuit for energizing said relay with said opposite polarity when said button. is in said normal position, whereby said relay is maintained in an energized position when, said button is restored to said normal position from a depressed position and said relay is dropped away when said button is restored to said normal position from said rotated position, and a traflic controlling device controlled by said neutral relay.

10. In a switch and signal control system for railroads, a track layout'providing a plurality of routes between entrance having normal and operated positions for said entrance and exit points, a signal having clear and stop aspects for a given entrance point for governing traffic through said track layout, indicator lamps capable of causing the emission of distinctive colored lights from the center of the and exit points, buttons button for said given entrance point, route establishing means responsive to the joint operation of said buttons for opposite ends of a route emanating from said signal for setting up that route and clearing said signal, circuit means for energizing a first of said indicator lamps to cause the emission of one color of light from said button for said given point whenever said signal is clear, another circuit means for energizing a secend of said indicator lamps to cause the emission of another color of light from said button whenever said signal is at stop and said button is in non-operated position, and means acting on said another circuit means for said second indicator lamp for periodically interrupting its energy to cause the flashing of that second lamp whenever said button is in its operated position to control said route establishing means but said signal is still at stop.

11. In a switch and signal control system for railroads, a track layout providing a route between first and second points, manually operable buttons for each of said points, a signal for said first point for governing traific through said track layout, indicator lamps included in said button for said first point capable of emitting light of distinctive color from said button, route establishing means responsive to the joint operation of said buttons for setting up a route through said track layout, circuit means for energizing a first of said indicator lamps to cause the display of one color of light whenever said signal is clear, and circuit means for energizing a sec- 0nd of said indicator lamps to cause the display of another color of light at all times when said signal is at stop.

12. In a traific controlling system for railroads; a power-operated track switch; a detector track section associated with said track switch; a signal for governing traflic over said track switch; a manually operable control switch having a normal position and a plurality of operated positions, said switch having a first contact closed only when said switch is in one operated position, a second contact closed when said switch is in said one operated position or in said normal position and opened only when said switch is in another operated position; a neutral relay; a pick-up circuit including said first contact for energizing said neutral relay whenever said switch is in said one operated position, a stick circuit including said second contact for maintaining said neutral relay energized when said button is in said normal position but is deenergized when said switch is in said another operated position; means controlled by said detector track section for opening said stick circuit upon the entrance of a train; and means controlled by said neutral relay for governing the clear and stop indications of said signal.

13. In a trafiic control system for railroads; a manually controlled button operable from a normal position to a rotated position in which it remains until manually restored to said normal position and also operable to a depressed position and a pulled-out position from said normal position to which normal position it is biased with respect to the push and pull movement; a

first contact operated by said button so as to be closed when said button is operated to its rotated position; a second contact operated by said button so as to be opened when said button is operated to its rotated position; a third contact closed when said button is operated to its depressed position; a fourth contact operated by said button so as to be opened only when said button is operated to its pulled-out position; a neutral relay having two windings; an energizing circuit for one of said windings including said first contact; a pick-up circuit including the other winding of said relay connected oppositely to said one winding and also including said second and third contacts; a stick circuit including said other winding and said second and fourth contacts; a power-operated track switch; a signal for governing traffic over said track switch; a detector track section for said switch; means for momentarily opening said stick circuit upon the entrance of a train into said detector track section; and circuit means controlled by said relay for governing the operation of said track switch and said signal.

14. In a trafiic controlling system for railroads; a track layout including at least one power-operated track switch for providing routes between an entrance point and a plurality of exit points; a signal at said entrance point for governing trafiic over said routes; a track section in advance of said signal; a control panel having an entrance button for said entrance point and an exit button for each of said exit points, said entrance button for said entrance point being operable from a normal position to a rotated position in which it remains until manually restored and being operable to a depressed position and a pulled-out position from the normal position to which it is biased; a first contact operated by saidbutton so as to be closed when said button is operated to its rotated position; a second contact operated by said button so as to be opened when said button is operated to its rotated position; a third contact closed when said button is operated to its depressed position; a fourth contact operated by said button so as to be opened only when said button is operated to its pulled-out position; a neutral relay having two windings; an energizing circuit for one of said windings including said first contact; a pickup circuit including the other winding of said relay connected oppositely to said one winding and including said second and third contacts; a stick circuit for said relay including said other winding and also including said second and fourth contacts; route establishing means rendered effective upon the picking up of said neutral relay and the operation of a particular one of said exit buttons for operating said power-operated track switch to establish a route between said entrance point and that particular exit point corresponding to the operated exit button and for clearing said signal; and means controlled by said detector track section for momentarily opening the stick circuit of said neutral relay upon the entrance of a train into said detector track section.

SEDGWICK N. WIGHT.

D I S C L A I M E R 2,150,868.Sedgwick N. Wight, Rochester, N. Y. INTERLOCKING SYSTEM FOR AILROADS. Patent dated March 14, 1939. Disclaimer filed May 18, 1940, by the assignee, General Railway Signal Company. Hereby enters this discla iIner by disclalming from claim 12 any trafiic 0 system except wherein said position of said manually operabl pulled out position, respectively.

[Ofiicz'al Gazette June 11, 1940.] 

